> Ha.
> And that's the difference Patrick!
> It was a tinkeling sound rather than a clicking sound!
> If you'd kept driving, like Wally gates did, or like Steve Byers
> did, or i did with a Sprite (many years ago), you would have just
> had a shrapnel dented cylinder head roof and piston!!
> Here is the problem......
> The top ring wears through the alloy piston, and the ring gap is
> worn and increased. The ring "flutters" in the worn ring groove. The
> ring breaks, and starts to erode the ring lands above and below, due
> to increased tolerances. The ring land above and below it is then
> eroded to the point of failure. The alloy ring land is no match for
> the fluttering steel ring.
> Then a chunk of the top (crown) alloy ring land parts company from
> the piston crown.
> Followed by the broken piece of steel ring.
> Then the clinking starts. The piece of steel ring bouncing around in
> the combustion chamber.
> Until it exits via the exhaust valve with an obvious clinking. And
> you hear it all the way down the exhaust system!.
> You just didn't drive it long enough for the clinking!!!!
> What does the top of your combustion chamber/ piston look like???
> Like its been Shot blasted with a square section piston ring??
> At least you know what the noise was Patrick. I still think the
> other issues will be cam followers/ cam and little ends.
> This issue seems to occur only on cars fitted with new rings fitted
> to old pistons, when the pistons probably should have been replaced,
> rather than re ringing.
> Best
> Chris
PS your top ring will be broken.
> Sent from my iPhone
>
> On 29/05/2011, at 9:12 PM, "Patrick and Caroline Quinn" <p_cquinn@tpg.com.au
> > wrote:
>
>> G'day
>>
>> Listers would recall the loud and expensive noises coming from the
>> engine of
>> the BN3/1.
>>
>> The engine is still in the car, but everything hanging off it has
>> now been
>> removed. Yesterday my eldest son and I removed the cylinder head.
>> It was a
>> struggle, but once the overdrive throttle switch was removed it was
>> possible
>> to lift the head, move it sideways and then away from the engine.
>>
>> At first glance everything appeared as it should be, but looking more
>> closely today, a 12mm by 5mm piece from the edge of the crown of
>> the No 2
>> piston was missing. Small bits of aluminium were embedded in the
>> top of the
>> piston and minor damage was evident in the combustion chamber. The
>> top
>> compression ring was intact hence the smooth but noisy running
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